The recording of electrical activity of the heart is known as an Electrocardiogram (ECG). An ECG measures the differential electrical signal between a pair of electrodes of an ECG device. A pair of electrodes of the ECG device is referred to as an ECG lead. Conventional methods of recording an ECG involve placing 10 adhesive electrodes on the chest, torso, and possibly the extremities of a patient to record different ECG leads derived from differential potentials between different combinations of the electrodes.
In a clinical environment, ECG machines to record multiple ECG leads have multiple ECG electrodes connected to an ECG device via electrical cables and clips. The multiple ECG leads enable a physician to “view” the heart from different directions. The different “views” of the heart may assist the physician in diagnosing a heart condition of the patient. This type of ECG setup however requires numerous accessories to connect the patient to the ECG device, such as disposable electrodes and ECG cables. Additionally, such a procedure requires expertise to setup and administer the ECG and may not be comfortable for the patient.
In some recent developments, a variety of Personal ECG Monitors (PEM) have been produced. In part, the PEMs seek to address the usability problem of traditional ECGs by using two metal electrodes embedded on the ECG device itself. The PEM operates to record an ECG by having the patient either hold the device in their hand or against their chest so that the metal electrodes of the device touch the patient's body. In this manner the PEM is able to effectuate a single ECG lead. However, PEMs are limited in their diagnostic capability since they typically do not measure more than one ECG lead. In many aspects, a single ECG lead is insufficient to detect some serious heart conditions (e.g., ischemia and infarction).